The present invention relates to an observation lens barrel for use in a microscope.
Generally, a microscope has a main body and an observation lens barrel attached to the main body.
The main body of the microscope has a stage for holding an object of observation and an objective lens set in opposition to the stage. The observation lens barrel is designed to guide the image of the object passing through the objective lens, selectively to, for example, the ocular lens or a photographing unit.
Recently, it is increasingly demanded that various auxiliary units, each having a special optical system, be attached to the observation lens barrel in accordance with the type of the object of observation. Among such auxiliary units are a scale-projecting unit and a looped optical path unit. The scale-projecting unit forms an image of a scale in the image of the object. The looped optical path unit achieves confocal observation of the object.
If the function of the lens barrel of the microscope is expanded so that various auxiliary units may be attached to the lens barrel, special optical systems must be incorporated into the lens barrel. However, this causes a problem in that the lens barrel will inevitably become taller and larger.
The present invention has been made in view of the foregoing. Its object is to provide a lens barrel for use in a microscope, which is small and can be readily expanded in function to hold various auxiliary units.